Electric switch



(No Model.) 3 Sheets-Sheet 1. J. J. WOOD. ELECTRIC SWITCH.

No. 537,515. Patented A r. 16 1895.

WITNESSES: INVENTOR:

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(No Model.) 3 Sheets-Sheet J. J. WOOD. ELECTRIC SWITCH. No. 537,515.,Patented Apr. 16, 1895.

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(No Model.) 3 Sheets-Sheet 3.

- J J WOOD ELECTRIC SWITCH.

No. 537,515. Patented Apr. 16, 1895.

INVENTOR: W M

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UNITED STATES PATENT OF ICE.

JAMES J. VOOD, OF FORT \VAYNE, INDIANA.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 537,515, dated April16, 1895.

Application filed November 12, 1894;. Serial No. 528,517- (N0 model.)

To all whom it may concern:

Be it known that I, JAMEs J. W001), a citizen of the United States,residing at Fort Wayne, in the county of Allen and State of Indiana,have invented certain new and useful Improvemements in Electric Switchesor Out-Outs, of which the following is a specification.

This invention relates to what are known as snap switches, or thosewhich move with a quick action to avoid drawing an are. In such switchesit is usual to provide an operating handle, and a spring which iscompressed by the initial movement of the handle, and the compression ofwhich stores up power tending to move the conducting member or bridge ofthe switch, the movement of which is resisted by a latch or catch, untilby a further movement of the operating handle this latch or catch iswithdrawn, thereby releasing the movable bridge and permitting it to flyquickly under theimpulse of the compressed spring to the oppositeposition. It is to switches of this character that my present inventionrelates.

The improved switch provided by my present invention comprises a fixedbase or support, stationary circuit connections or terminals mountedthereon, and a rotatively movable circuit-closing or breaking memberwhich I will call the bridge, and which according to its position, makesor breaks electric connection between the opposite circuit terminals.This bridge is capable of rotating in only one direction, moving analiquot part of a revolution at each movement. An operating handie isprovided having an axial spindle, and connecting with the bridge throughthe medium of a spring which tends constantly to turn the bridgeforward. To resist this tendency and lock the bridge in position, afixed ratchet is provided attached to the stationary base, and to thebridge is pivoted a pawl engaging this ratchet and provided with a tailconstructed to serve the double purpose of insuring the engagement ofthe pawl and of receiving the thrust from an arm on the operatingspindle for disengaging the pawl.

My invention resides chiefly in the peculiar and novel construction ofthis ratchet and pawl or locking device, and the means for disengagingit.

It also relates to other features in the construction of the switch, aswill be hereinafter set forth.

Figures 1 to 7 illustrate a switch or cut-out for arc. lamp circuitsembodying my invention, and Figs. 13 to 15 illustrate a field-magnetcut-out for dynamos embodying part of my invention. Fig. 1 is a frontelevation partly in vertical mid-section, the front plate or cap and theoperating handle being removed. The view also shows diagrammatically theconnections with the main line circuit and with the loop,inclnding theare lamp or lamps which are to be cut out by the switch. Fig. 2 is atransverse mid-section through the switch. Fig. 3 is an elevation of theoperating handle and its spindle removed. Fig. 4 is a rear view of therotary bridge partly broken away in section. Fig. 4 shows in face andedge view the central plate or hub of this bridge. one of the conductingstrips of this bridge. Fig. 6 shows in plan and side view the ratchet orstationary locking plate. Fig. 7 shows the locking pawl detached. Figs.8 to 12 are onlarged views showing the successive positions of theratchet and pawl and operating spindle on a larger scale. Fig. 13 is aface view of the field-magnet switch, the top plate being partly brokenaway and the operating handle being removed. Fig. 14 is a transversesection thereof. Fig. 15 shows a face and edge view of the rotaryconducting bridge.

Referring to Figs. 1 to 12, let A designate an inclosing case, designedto protect the 0perative parts from the weather, and having a closefitting cover A.

113 is an insulating base, preferably of marble, and fastened within thecasing A.

O O are the main line binding posts, the mainline wires a a beingintroduced through bushed openings in the case in a well known manner. 7

O C are the binding posts of the branch line or loop, the wires ofwhich, lettered a, enter the case obliquely through bushed openings asshown. The loop or branch circuit a contains one or more electric arclamps which it is desired to cut out of the main circuit by means of theswitch arranged as usual. nected with each of the binding posts 0 O is aterminal contact spring D, and with each Fig. 5 shows in edge and sideview Conof the binding posts O is connected a terminal contact spring D.These four springs press against the periphery of a disk E, whichconstitutes what I call the bridge. This disk is made of insulatingmaterial, preferably porcelain, and has conducting strips F F let intoit on opposite sides, each strip extending far enough around on theperiphery of the bridge to form aconnection between any two adjoiningsprings D or D. WVhen in the position shown in Fig. 1, the strips F Feach connect one of the springs D with one of the springs D, so that theloop circuit a is cut in serially with the main line; but by turning thebridge E a quarter revolution,the strips F are moved to such positionthat the lower one will form a'direet bridge or shortcircuit between thetwo line terminal springs D D, thereby cutting out the loop a. On theface of the bridge are marked the words On and Off, so that when theswitch is so turned that the loop line is on the circuit, one of thewords On shall when the cover A is in place be exposed through anopening shown by the dotted lines G in Fig. 1, and when the switch isturned to cut out the loop circuit, one of the words Off will :showthrough this opening, in the well known manner.

The switch is turned by an operating handle 11 (Fig. 2) of insulatingmaterial, fixed on the end of a rotative spindle I (Fig. 3) which passesthrough the center of the bridge E, and has a bearing in a sleeveb. Thissleeve b constitutes the shank of a ratchet disk or plate I, which isshown detached in Fig. 6.

This ratchet disk is fixedly attached to the base B, being clampedthereto by a nut c (Fig. 2) screwing'on the threaded end of the sleeve1). To insure against the rotation of the disk, it has a pin 01 which isseated in a hole drilled in the base B. The disk J is formed withratchet teeth or lockingprojections e c of any suitable number,preferably four, and equidistantly arranged. Theearthenware bridge E ismolded with asocket in its underside, into which socket fits .a plate K,shown detached in Fig. t. Toinsure that this plate and the bridge shallturn together, the plate is formed with end projections 70 which fit incorresponding recesses in the socket. The plate is fastened'to theearthenware by a screwf passing through the earth enware and screwinginto a threaded :hole in the plate. The plate has a pin g fixed in itand projecting to both sides. The plate is formed with a central hole Itfittin'g'thespindle I, so that the bridge is guided upon the spindle inits rotative movements. Ooiled around the spindle is a spring L, one endof which engages a pin in the spindle, and the other end of whichengages the pin g projecting upwardly from the plate K. The direction ofthe spring is such that it tends to rotate the bridge forward (see arrowin Fig. 1), the spring reacting with a backward thrust against thespindle. A pawl or'movable l0cking plate M, shown detached in Fig. 7, ismounted between the plates K and J, being pivoted on the downwardlyprojecting portion of the pin g, which enters a hole g in the pawl. Thepawl has two arms, one of which M maybe called the locking arm, and theother M the releasing arm. These arms project beyond the rotative centerand on opposite sides of the spindle I, as shown in Figs. 8 to 12.

Referring to Fig. '7, the locking arm M is formed with a notch m forengaging one of the teeth 6, one side of the notch constituting thelocking face at of the pawl. The other arm M has a cam face 19. Betweenthe two arms projects a radial arm or pin 1' projecting from the spindleI. The lower end of the spindle I has a pin it put through it after itis inserted in place, which projects beneath the nut c and prevents thelifting or pulling out. of the spindle.

The operation may now be understood. Figs. 1, 2 and 8 show the parts ina position of rest. The tension of the spring L is pressing the bridge Eforward in the direction of the arrow at; in Figs. 1 and 8, which isresisted by the pawl M, the locking face at of which is in engagementwith the tooth e in Fig.8. The reaction of the spring against thespindle tends to rotate it in a contrary direction, and thence swingsits arm 1 around against the arm M of the pawl in the direction of thearrowz in Fig.8. The end of the arm I strikes the tangential inner faceof the pawl arm M, and thereby serves to press this arm outward and holdthe notch m thereof in firm engagement with the tooth 6. Now in case itis desiredto throw the switch, the person operating it will turn thehandle II to the-right, and as soon as he begins to turn it the reactionof the spring no longer presses through the arm I against the pawl M,but this reaction comes against the hand of the operator. As he turnsthe spindle he swings the arm I around until it strikes the pawl arm Mand upon con tinuing the movement it thrusts this pawl arm away in themanner shown in Fig. 9, thereby rocking the pawl M until the lockingface m is slid past the tooth c and disengages itself from the latter.It is shown in Fig. 9 at the instant of disengagement, the

arrows indicating the direction of motion of the parts up to thisinstant. Immediately upon the disengagement, the tension of the springbecomes effective to rotate the bridge .E forward, and it instantlyflies over with a rapid and forcible movement of one-quarter revolution.Fig. lOshows it in the course of this movement. As soon as this movementbegins, the cam face 13 of the pawl arm M comes in contact with theinner face of the tooth c and since this cam face 29 is thrust into aneccentric position by the releasing movementasshown in Fig. 9,itscontact with the tooth c thrusts this face inward and thereby oscillatesthe pawl upon its pivot 9 while it is advancing, so that the lockingface m is thrust outward into position to certainly encounter the toothe as is apparent from examining Fig. 10. Fig. 11 shows it at the instantwhen it encounters this tooth. The bridge is still moving, carrying thepivot g around in the are denoted by the arrow 3 which wedges thelocking face an against the abutting face of the tooth c and by reasonof the obliquity of the locking face relative to the direction ofmotion,thrusts it outward in the direction of arrow 11, which motioncontinues until the pawl is fully seated with its notch m in completeengagement with the tooth as shown in Fig. 12. When thus fully seated,the rotation of the bridge is abruptly stopped. Then when the operatorreleases the handle,the tension of the spring causes the spindle to turnbackward and press the pin 1 again against the arm M of the pawl, asshown in Fig. 12. The parts being symmetrical, any future advancemovements mayoccur in preciselythe same manner.

It will be understood that the disk J constitutes essentially astationary ratchet wheel having internal teeth, the projections e econstituting these teeth, the portions between the most salientinternally projecting portions of the teeth being cut way. The pawl inan ordinary internal ratchetwould consist of the portion from the pivothole g to the locking face m. I have added to this pawl the oppositelocking arm M with its cam face 1), and also the prolongation or arm Mwhich receives the thrust of the arm I to hold the ratchet normallylocked. The arm M may be called the locking arm and the arm M theunlocking arm.

The construction of the earthenware bridge E with its conducting stripsF, presents novel features. It would be difficult to find any screwfastenings or similar means for attaching the strips to an earthenwaredisk, andI have therefore devised the construction shown in Figs. 4 and5. The strips F are punched out at q qto form ears 7" 1', which turninwardly as shown in Fig. 5. The earthenware disk is molded withrecesses or cavities s s (Fig. 4), four in number, one pair of thesecavities bein g spaced apart just widely enough to receive the ears 4" rof one metal strip into them. In applying the strip, it is sprung orbowed outwardly to press its ears apart sufficiently to enter them intothe cavities s, and upon releasing it the converging form of the earsdraws the strip tightly against the earthenware disk. The fastening thusmade is very secure, very simple in construction, and the assembling ofthe parts is very readily effected.

Figs. 13, 14 and 15 show a construction designed particularly as acut-out for short-circuiting the field-magnet coils of a dynamo, inorder thereby to break down the field of force and render the machineimpotent when necessary. The construction of the snap devices is exactlythe same as in the switch already described. The sole difierences are inthe construction of the bridge E, which is here lettered E, and thecircuit terminals. There are two binding posts lettered 0 0 each ofwhich is formed with projecting ears D adapted to embrace betweenthemthe end of the bridge-piece E ,as shown in Fig. 14. This bridge F.is shown detached in Fig. 15. It consists simply of a metal platepivoted at its middle on the spindle I, in place of the plate K in theprevious construction. It has the same pin g, and otherwise operates inthe same manner mechanically as the bridge already described. The normalposition of the bridge is that shown in dotted lines in Fig. 13, whereit stands midway between the binding posts and out of contact with them.To shortcircuit the field coil, the operating handle H is turned tocause the switch to snap to the position shown in full lines, where thebridge forms a short-circuit or conductor between the two binding posts0 The insulating base B is preferably of marble, and the switch insteadof being boxed in as in the previous construction, is open, with simplya marble top-plate P mounted on four posts. The shunt circuit wires toto enter from the back of the base-plate B and pass through the tubularfastening shanks of the binding posts.

Myinvention is susceptible of considerable modification Withoutdeparting from its essential features. Many constructions of circuitterminals are known in the electric art which might be substituted forthose shown, and if necessary the conducting portions of the bridgemight be modified to better adapt them to such terminals, or to adaptthe switch to any particular action desired.

The bridge might be greatly varied in construction, this name havingbeen adopted by me in this specification to designate any intermittentlyrotative part adapted to effect in connection with suitable circuitterminals the making and breaking of a circuit, or other circuit changesor commutations.

The actuating spring may be otherwise arranged, and the particularconstruction of the ratchet and pawl may be varied provided the sameessential operation be retained, and other changes may be made notinconsistent with the spirit of my invention.

I claim as my invention the following-defined novel features,substantially as hereinbefore specified, namely:

'1. The combination in an electric switch having anintermittently-rotating bridge, of an operating handle, a springinterposed between the handle and bridge, and a locking mechanismconsisting of a stationary internal ratchet, a two-armed pawl pivotallyconnected to the bridge, having locking and unlocking arms projecting011 opposite sides, and an operating arm connected to the handle andarranged between said arms to bear against the unlocking arm todisengage the pawl from the ratchet and to bear against the locking armto hold the pawl engaged with the ratchet.

2. The combination in an electric switch having anintermittently-rotating bridge, of an operating handle, a springinterposed between the handle and bridge, and a locking mechanismconsisting of a stationary internal ratchet, a pawl pivotally connectedto the bridge, having locking and unlocking arms projecting on oppositesides,and the unlocking arm formed with a cam-face adapted to engage theratchet teeth during the forward movements of the bridge and direct thelocking arm into engagement with the next ratchet tooth in advance, andan operating arm'connected to the handle and arranged to act against theunlocking arm to disengage the pawl.

3. The combination in an electric switch having anintermittentlyrotating bridge, a rotative axial spindle, an operatinghandle thereon, a spring interposed between the bridge and spindle, astationary ratchet, and a two-armed pawl pivotally connected to thebridge, with its arms projecting to opposite sides of the spindle, andan operating arm projecting from the spindle between said arms of thepawl and adapted to bear against either to essentially the efiect setforth.

4. The combination in a switch of a rotative bridge, a spindle I havingan arm Iand handle H, a spring L, a fixed ratchet J, and a pawl Mpivoted to the bridge and having a locking face m and a cam-face pcoacting with the teeth of said ratchet and actuated by said arm I, tosubstantially the effect set forth.

5. The combination in a switch of a rotative bridge, a spindle I havingan arm I and handle H, a spring L, a fixed ratchet J, consisting of adisk having projecting teeth 6, and a pawl M pivoted to the bridge,having two arms projecting to opposite sides of said spindle and actedon by said arm I, with a cam-face p on one arm and a locking notch m inthe other.

In witness whereof I have hereunto signed my name in the presence of twosubscribing witnesses.

JAMES J. WOOD.

Witnesses:

CHAS. O. MILLER, WILLARD KNIGHT.

